Radar transmitters of radar sensors are operated using a high-frequency source (an oscillator). The high-frequency source operates either directly on the frequency emitted in a regulating loop or operates at a lower frequency which is multiplied to the frequency to be transmitted. The two following techniques are known for distribution of the transmission power for long-range radar (LRR), medium-range radar (MRR) and short-range radar (SRR). A single-beam radar having electromechanical beam slewing equipment and/or a passive distribution network may be used. In the latter case, amplifiers may additionally be provided to compensate for distribution losses.
PCT International Patent Publication No. WO 2007/052247 describes a radar system for automatic driving by providing a multiplex for distributing a reference signal among four transceiver units. Each transceiver unit includes four antenna outputs for one antenna each of a phased-array antenna field. Each antenna is supplied with transmission power by a separate phase-scanned injection-locked push-push oscillator (PS-IPPO). The phase of each of the PS-IPPOs is synchronized in the pull range by a cascade of upstream PS-IPPOs with a reference signal from a reference signal generator. Outside of its pull range, the respective PS-IPPO is a free-wheeling oscillator. Injection-locked oscillators have the disadvantage that it is difficult to influence a time characteristic of the tracking of the oscillator.